Lightroom 6/Lightroom CC (same thing) came out last week and has several nice features including performance. Installing it at home on my machine running Windows 8.1 with AMD Radeon HD 6950 I was hoping to see how the new GPU performance would perform. Unfortunately the GPU was failing to initialize properly.
After talking to a friend, who also had a much older AMD /ATI video card, I soon discovered that the 14.4 driver works just fine with Lightroom 6/CC but, the 14.9, 14.12 and beta do not.
If you want to use acceleration, and you do because its nice, you'll need to revert back to this older driver.
Why they release a product that only works with a year old video driver, I do not know.
Just to be clear the following DO NOT WORK.
But this one